module Hello_module
    implicit none
    save
    private

    public  ::  hello_w

contains
   subroutine hello_w
    integer i
    integer j
    print *, 'Enter Number'
    read *,i
    if(i<0 .or. i>20) then
        print *, 'Ridiculous Number'
    else
        do j=1,i
            print *, 'Hello World'
        enddo
    endif
   end subroutine
end module
